The study is conducted in two parts (Part A and B). The main purpose of this study is to look at the amount of the LY3437943 that gets into the blood stream and how long it takes the body to get rid of it when given subcutaneously (SC, under the skin) in the upper arm and thigh compared to the abdomen in healthy participants with high body mass index (BMI) in Part A. In Part B, the participants receive LY3437943 intravenously (IV, through a vein) where the safety and tolerability of LY3437943 are evaluated and information about any side effects experienced will be collected. For each participant, the total duration of the study will be approximately up to 157 days and 99 days for Part A and Part B, respectively.

Inclusion Criteria:

• Healthy males or females of nonchildbearing potential as determined by medical history, physical examination, and other screening procedures
• Body mass index (BMI) between 27.0 and 45.0 kilograms per meter squared (kg/m²), inclusive
• Are agreeable to receiving study treatment by injections under the skin or through a vein.

Exclusion Criteria:

• Have a history of diabetes (except gestational diabetes) or current diagnosis of diabetes (any form)
• Have a significant history of, or presence of, any of the following disorders capable of significantly altering the absorption, metabolism, or elimination of drugs
• Have known allergies to LY3437943, related compounds, or any components of the formulation
• Smoke more than 10 cigarettes or use the equivalent tobacco, smoking-cessation products, nicotine-containing products, or e cigarettes (nicotine and non nicotine) per day.
• Is a known user of drugs of abuse